315 Dartmouth was designed by Charles Brigham of Sturgis and Brigham, architects, and built in 1870 by Weston & Shepard as the home of banker Hollis Hunnewell and wife, Louisa (Bronson) Hunnewell. They previously had lived at 145 Beacon. They also maintained a home in Wellesley.

Louisa Hunnewell purchased the land for 315 Dartmouth on April 3, 1869, from attorney Peleg Whitman Chandler. The original parcel had a frontage of 78 feet on Marlborough and consisted of three lots Peleg Chandler had purchased from the Commonwealth of Massachusetts on March 30, 1865, April 6, 1865, and April 8, 1865. The Hunnewells had their home built on the corner, at 315 Dartmouth, with a 53 foot frontage on Marlborough. On November 2, 1872, Louisa Hunnewell sold the remaining 25 feet to the east to John Fisher Farrington, a carpenter and builder, who built 148 Marlborough on the lot. The deed included a requirement that any house built at 148 Marlborough could be no higher and no deeper than the Hunnewell’s house at 315 Dartmouth.

In January of 1872, Hollis Hunnewell purchased the corner lot at Commonwealth and Dartmouth, across the alley from 315 Dartmouth. In 1876, his brother-in-law, architect Robert Gould Shaw, designed two houses on the lot at 303 Dartmouth and 151 Commonwealth. Robert and Isabella (Hunnewell) Shaw lived at 151 Commonwealth; Arthur Hunnewell (brother of Hollis Hunnewell and Isabella Shaw) and his wife, Jane (Boit) Hunnewell, lived at 303 Dartmouth.

During the night of December 18-19, 1876, 315 Dartmouth was seriously damaged by a fire which resulted in the death of Annie O’Hara, a kitchen maid, who was trapped on the top floor.

As originally designed, 315 Dartmouth had a mansard roof above two stories and a basement. It was probably as part of the reconstruction following the fire that the roof was expanded into a full story at the Dartmouth-Marlborough corner and an additional story within a mansard roof constructed. It probably also was at this time that a similar modification, lower in height, was made to the mansard above the bay on Dartmouth to the south of the entrance.

Hollis Hunnewell died in June of 1884. Louisa Hunnewell continued to live at 315 Dartmouth.

During the 1886-1887 winter season, Louisa Hunnewell was living elsewhere and 315 Dartmouth was the home of banker Eugene Van Rensselaer Thayer and his wife, Susan (Spring) Thayer. They previously had lived at 23 Commonwealth, and by the next season were living at 151 Commonwealth and 315 Dartmouth was once again Mrs. Hunnewell’s home.

315 Dartmouth, 1883 Bromley map

315 Dartmouth, 1888 Bromley map

Sometime between 1883 and 1887, a one-story plus plus basement wing was added, extending the house to the edge of alley between Marlborough and Commonwealth. The addition does not appear on the 1883 Bromley map, but can be seen on the 1887 Sanborn map and the 1888 Bromley map.

Louisa Hunnewell continued to live at 315 Dartmouth and in Wellesley until her death in November of 1890.

During the 1890-1891 winter season, 315 Dartmouth was the home of wholesale dry goods merchant Joseph Stevens Kendall and his wife, Ellen (Ling) Kendall. During the previous season, they had lived at 61 Commonwealth, and by the 1891-1892 season, they had moved to 8 Gloucester.

315 Dartmouth (ca. 1876); detail from photograph of the south side of Marlborough, courtesy of Historic New England

By the 1891-1892 winter season, 315 Dartmouth had become the home of Hollis and Louisa Hunnewells’ son, Hollis Horatio Hunnewell, and his wife, Maud Somerville (Jaffray) Hunnewell. They had married in April of 1891 and 315 Dartmouth probably was their first home together. They also maintained a home in Wellesley.

Hollis Horatio Hunnewell’s, sister, Charlotte Bronson Winthrop Hunnewell, lived with them at 315 Dartmouth, as well as in New York City and at her home, Gull Rock, in Newport. She married in October of 1894 to Victor Sorchan, after which they lived in New York and Newport (they divorced in December of 1920 and she re-married in January of 1921 to Dr. Walton Martin, a New York surgeon; in the early 1920s, they built Hidden Valley Castle in Cornwall, Connecticut).

Hollis and Maud Hunnewell continued to live at 315 Dartmouth during the 1893-1894 winter season, but appear to have made Wellesley their year-round home thereafter.

During the 1894-1895 winter season, 315 Dartmouth was the home of cotton mill owner Horatio Nelson Slater and his wife, Mabel De Carteret (Hunt) Slater. They had lived at 293 Beacon in 1893. They also maintained homes in Magnolia and in Webster, where several of his cotton mills were located.

The Slaters continued to lived at 315 Dartmouth during the 1895-1896 winter season, but moved thereafter to 17 Gloucester.

315 Dartmouth was not listed in the 1897 Blue Book.

During the latter part of the 1897-1898 winter season, 315 Dartmouth was the home of Henry Denison Burnham and his wife, Johanna (Heckscher) Burnham. They had spent the earlier part of the season in Newport. In 1896, they had lived at 183 Marlborough. He was a trustee of estates. They continued to live at 315 Dartmouth in 1899.

The house was not listed in the 1900 and 1901 Blue Books.

On May 7, 1901, 315 Dartmouth was purchased from Hollis Horatio Hunnewell by Thomas Jefferson Coolidge. He was a recent widower, his wife, Mehitable (Hetty) Sullivan (Appleton) Coolidge, having died in March of 1901. At the time of her death, they were living at the Tudor, at the corner of Beacon and Joy Streets. He also maintained a home on Coolidge’s Point at Manchester.

T. Jefferson Coolidge was the former treasurer of the Boott Mills in Lawrence, and was an investor in textile mills, banks, and railroads. In 1890, he had joined his son, Thomas Jefferson Coolidge, Jr., in founding the Old Colony Trust Company. He served as Ambassador to France in 1892 and 1893.

Before moving to 315 Dartmouth, he had it remodeled extensively. A news article from the period describes the remodeling as follows:

“A remodeled house is not always successful, but that cannot be said of Mr. Jefferson Coolidge’s new mansion on Dartmouth street. It occupies one of the most desirable locations in town, and may proudly join the procession of ‘palaces’ which Boston has gathered under its wing during the last two or three years. I hear an immense amount of money has been spent on changing this Hunnewell estate into what is ostensibly three houses in one for our former ambassador to France, and whose ideas have been rather Parisian than Venetian or colonial in regard to reconstruction and decoration…”.

By the 1903-1904 winter season, T. Jefferson Coolidge had been joined at 315 Dartmouth by his daughter, Marian Appleton (Coolidge) Sargent, the widow of attorney Lucius Manlius Sargent. She previously had lived at the Empire at 333 Commonwealth; at the time of her husband’s death in November of 1893, they had lived at 184 Beacon.

In October of 1903, T. Jefferson Coolidge purchased 148 Marlborough, which he leased to Rear Admiral Francis Tiffany Bowles and his wife, Adelaide Hay (Savage) Bowles. In May of 1908, Adelaide Bowles purchased the house.

Thomas Jefferson Coolidge died in November of 1920. 315 Dartmouth was inherited by Marian Sargent and on December 20, 1921, she transferred the property to the trust established for her benefit under her father’s will. By the 1921-1922 winter season, she had moved to the Hotel Agassiz at 191 Commonwealth.

On April 7, 1922, 315 Dartmouth was purchased from Marian Sargent’s trust by Charles Fanning Ayer. He and his wife, Sara Theodora (Ilsley) Ayer, made it their home. They previously had lived at 127 Commonwealth. They also maintained a home, Juniper Ridge, in Hamilton.

Charles (“Chilly”) Ayer was an attorney and the son of Frederick Ayer, a patent medicine manufacturer and major textile mill investor who, with his son-in-law, William Madison Wood, had founded the American Woolen Company, which eventually grew into the largest woolen manufacturing company in America.

On March 30, 1932, Charles Ayer transferred the property into a trust for the benefit of Theodora Ayer and their children.

Theodora Ayer died in January of 1945. Charles Ayer continued to live at 315 Dartmouth and in Hamilton, and in March of 1946 married again, to Anne Phillips, formerly his secretary. They continued to live at 315 Dartmouth until 1951.

On January 14, 1952, 315 Dartmouth was purchased from the Ayer trust by the Douglas A. Thom Clinic for Children. The clinic remained there until 1993.

On September 1, 1993, the house was purchased from the clinic by Dr. Bernardo Nadal-Ginard, a pediatric cardiologist and professor at Harvard Medical School, and his wife, Dr. Vijak Mahdavi, also a professor at Harvard Medical School. They were noted collectors of modern art.

On January 10, 1997, 315 Dartmouth was acquired by general construction contractor Jay M. Cashman, as trustee of the 315 Dartmouth Trust.

In September of 1997, he applied for (and subsequently received) permission to convert the house from a doctor’s office, consulting room, and day care center into a single-family dwelling. In January of 1999, he applied for (and subsequently received) permission to construct an interior garage in the basement of the house.